wumpus

Copperbox revision 1881.

Minor corrections to Wumpus-Core - Core.Text.Base is now exposed in the Wumpus.Core shim module.

Work towards replacing the Advance text-with-metrics prototype in Wumpus-Basic. I now have a primitive function singleLine (which will be renamed in due course) that draws a line and returns its accurate bounding box. Advance should be replaced with code that uses this primitive.